Electric-current regulator



April 5 1927. 1,623,492

T.P.PETER$ON ELECTRIC CURRENT REGULATOR Filed Nov 6, 1925 2 Sheets-Sheet 1 Fl E- I- A ril 5 1927. 7 p T. P. PETERSON ELECTRIC CURRENT REGULATOR Filed Nov. 6, 1925 2 She.ots-Sheet 2 Fl E E F I .E 7 1 7; M i I 12 AM As" 2;

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Patented Apr. 5, 1927.

I UNITED STATES PATENT OFFICE.

ELECTRIC-CURRENT REGULATOR.

Application filed November This invention relates to those regulators for electric currents which operate by auton'iatically increasing a resistance inserted in the circuit, when the current itself is increased; and it consists in the novel construction and combination of the parts hereinafter fully described and claimed.

In the drawings, Figure 1 is a side view of a regulator constructed according to th s invention and showing the casingv and a portion. of the resistance coil and other parts in section. Fig. 2 is a plan view of the same with the cover and other parts removed. Fig. 2- is a detail side view of the freeend portions of some of the spring contact arms, and is drawn to a larger scale. Fig. 4 is a plan view of the same. Fig; 5 is a cross-section, taken on the line 5- 5 in Fig. 3. Fig. (5 is a side view, similar to Fig. 1, but shows a modification of the resistance coil., Fig. 7 is a plan view of the parts shown in Fig. 6, with some parts removed.

A suitable casing 10 is provided for holding the regulating devices, and an electromagnet 12 is arranged vertically in the casing. An armature lever 14 is pivoted between its ends in the casing bya. pin 15, and an armature 16 is secured to one end of this lever over the core of the electro-magnet. The armature lever 14 is insulated, or is formed of insulating material, and a contact piece 17 is secured to the otherend of it from the armature. Electric current is con ducted to the contact piece 17 by wires 18 and a binding post 19.

Spring arms 20 are provided, and are arranged in a series one above another. These spring arms are secured at one end to a. support or post 21 formed of insulating mate rial, or are otherwise insulated and supported so that their free ends may move up and down pivotally. The free end of each arm 20 is provided with a contact piece 22 which is secured to it, and the contact pieces are arranged one above another and normally directly in circuit with each other and with the contact piece 17 of the armature lever. The contact piece of the lowest arm of the series rests on an insulated contact piece 24 secured to the casing 10. A Wire 25 connects the stationary contact piece 24 with the coil of the electro-magnet 12, and the current is led away from the said coil through wires 26 and a binding post 27.

The contact pieces are held directly in circuit with each other by means of insulated e, 1925. Serial No. 67,293.

springs 28 secured at their lower ends to the casing, and connected to a crossbar 29 on the armature lever 14 by eye-bolts 30 having nuts 31 for adjusting the springs. The con-- tact pieces inayhowever be held in circuit by any other approved means besides the springs 28.

A resistance coil 35 is provided, and is supported by the contact pieces 22. Each contact piece is secured to-a separate convolution of the coil 35. The coil may be continuous, and may have the contact pieces secured to its convolutionsin any approved. way, or the convolutions may be formed of separate portions which have their ends se cured in holes in the cont-act pieces. Each springarm 20, except the top one of the series, has a'lifter or link 36 secured to it, and extending over the arm next above the one which supports it.

These lifters or links are formed of insulating material, or are otherwise insulated from the arms, and they permit each arm to be lifted to a predetermined extent, and they are arranged so that they operate in succession, each arm being arranged to raise the,arm next below it in the series.

When the current through the regulator is increased over a predetermined amount, the

electro-magnet attracts its armature and.

overcomes the tension of the springs 28. lVhen the contact piece of the top arm is lifted clear of the contact piece next beneath it the current is obliged to pass circuitously around the top convolution of the resistance coil, to reach the wire 25 and the electromagnet instead of being short-circuited. The arms are raised one after another in succession by the armature lever, and the convolutions are included in the circuit one after another until a sufficient resistance has been placed in the circuit to compensate for the increased current supplied to the regula tor.

In the modification shown in Figs. 6 and 7 a resistance coil is provided. This coil is insulated and its upper end is connected to the inlet wire 18 and its binding post. The lower end of the coil 45 is connected to the wire 25 and through it to the coil of the electro-magnet 12. The armature lever 44 has the armature 16 at one end, and its otherend is connected to the top convolution of the coil 45 by a bolt 46. The convolutions of the coil 45 are normally held in contact with each other by a spring 48 secured to the arn'iature lever and to the casing, so that the current is normally short-circuited through the resistance coil and does not have to travel circuitously around its convolutions.

hen an increase of current operates the armature lever the convolutions of the resistance coil are raised out of contact with each other in succession, so that the current has to pass circuitously around them. The top convolution is raised first, and the raising of the convolutions is provided for in any approved way, as by making the material of the coil of different area, density or temper at successive points in its length, so that the coils may be separated in regular order. The weight of the upper convolutions upon the lower convolutions also prevents the lower convolutions from being raised first, but the coil may be made so that any convolution may be raised first, as the'dcvice will operate irrespective of the precise order in which the convolutions are 'aised to increase the length of the circuit and the resistance of the coil as a whole. The resistance coil &5 may advantageously be made rectangular in cross-section so that its convolutions may have good contact with each other when short-circuited.

What I claim is:

l. A variable resistor for an electric current regulator, comprising a helical coil, contact pieces secured one to each convolution of the coil and arranged one above another and normally short-circuiting the said convolutions, a stationary support arranged on the opposite side of the axis of the coil from the said contact pieces, insulated spring arms supporting the contact pieces from the sald support, and means for separating the contact pieces one after another to constrain the current to pass around the convolutions pertaining to them.

2. An electric current resistor as set forth in claim 1, and provided with a spring device which normally depresses all the spring arms and holds the contact pieces directly in circuit with each other.

3. A variable resistor for an electric current regulator, comprising a helical coil, a series of superposed contact pieces secured to the convolutions of the helical coil and normally short-circuiting them, pivotally movable arms supporting the said contact pieces, lifting devices connected with the said arms so as to raise them in succession, and an operating device connected with the con tact piece at one end of the series and ati'ording a means for sepa 'ating the contact pieces in succession.

4. An electric current resistor as set forth in claim 3, the said lifting devices being links secured to the arms and engaging with the next arms in the series so that each arm is raised in succession by the arm next above it. p

5. An electric current resistor as set forth in claim 3, the said arms being insulated spring arms and having the said contact pieces secured to their free ends.

In testimony whereof I have afiixed my signature.

THEODORE P. PETERSON. 

